1. Field of the Invention
This invention relates to a method and device for controlling a shock absorber so as to demonstrate a remarkable shock absorbing effect on objects having a wide range of kinetic energies.
2. Description of the Prior Art
As buffers for absorbing a shock which arises in stopping an object having an inertia, the following shock absorbers have heretofore been employed:
(1) Shock absorber using the elasticity of a material PA0 (2) Shock absorber using the viscosity of a fluid PA0 (3) Shock absorber using the dynamic pressure of a liquid PA0 (4) Shock absorber using the frictional force PA0 (5) Shock absorber using the plastic deformation of a metal
(a) Metal spring shock absorber PA1 (b) Rubber shock absorber PA1 (c) Air spring shock absorber PA1 (d) Fluid spring shock absorber PA1 (a) Constant pressure valve type shock absorber PA1 (b) Fixed orifice type shock absorber PA1 (c) Variable orifice type shock absorber
In any of such prior-art buffers, however, the object having an inertia comes into contact with a movable part for shock absorption and then the movable part is moved, whereby a shock absorbing force develops for the first time. Therefore, in case where the kinetic energy of the object is high, an impact stress at the contact between the object and the movable part becomes very high to adversely affect both the object and the movable part.
The prior-art devices lack in a function for the position control of the object, and therefore have the disadvantage that an accurate position control is impossible. Accordingly, such operations as automatically grasping the object stopped by the movable part and transferring it to another place are impossible.